As is well known, various processes and catalysts exist for homopolymerization or copolymerization of olefins. For many applications it is of primary importance for a polyolefin to have a high weight average molecular weight while having a relatively narrow molecular weight distribution. A high weight average molecular weight, when accompanied by a narrow molecular weight distribution, provides a polyolefin or an ethylene-.alpha.-olefin copolymer with high strength properties.
U.S. Pat. No. 5,264,504 discloses certain monocyclopentadienyl metal compounds having an amido radical with an aliphatic or alicyclic hydrocarbyl moiety attached thereto through a primary or secondary carbon atom. EPO 416,815 discloses certain monocyclopentadienyl metal compounds which are activated with an alumoxane cocatalyst. U.S. Pat. No. 5,064,802 discloses certain monocyclopentadienyl metal compounds which are activated with a non-coordinating compatible anion of a Bronsted acid salt.